Drupal 8.x

I have a form containing a Drupal 8 #table element, populated in a loop. Here is the relevant snippet of the buildForm method:

How to add Image plugin for CKEditor?
http://ckeditor.com/addon/image

I'm new to D8 and working on a module that needs a custom field type. I'm not exactly sure of the right way to save data that I add to the fieldSettingsForm when i create my fields. I couldn't find any documentation on this, or any obviously named methods to override, so what is the correct way to go about it? For example if i create a fieldSettingsForm as so, how do i save the user input? and how do i get that to set the default value in future?

I'm learning Drupal 8, and wanted to install Drupal 8 on my Ubuntu 15.10
desktop inside an isolated LXC container. It's easy, but maybe not as easy as
it should be, so I wrote a little script demonstrating how to do it. It's at

https://github.com/dankegel/d8demo

The core idea is just using composer to download and drush to 'install',
but there were a few gotchas along the way. I hope the script is useful for others.

Hello,
I'm creating a content type which contains a field of type Image. Editing this field I see there's a File directory field, whose description is: "Optional subdirectory within the upload destination where files will be stored. Do not include preceding or trailing slashes.".
I would like to call this directory with the Title of the content the user is creating.

I have installed the latest version of Drupal (8.0.1). Tested it, it worked, I installed several by-default-disabled modules and again it worked. BUT, when I create a new folder for theme, and start the process of new theme, the site breaks down and throws "The website encountered an unexpected error. Please try again later.". It has tired me out figuring out what the problem is, here are more info:

Problem Conditions: starting to create a new theme OR editing page.html.twig of the existing default theme.